Process for purification of waste waters from aromatic amines

摘要

The present invention relates to chemical processes for purification of industrial waste waters from aromatic amines. The process of the invention is characterized in that into waste waters aromatic di- or polyisocyanates are introduced in a molar ratio with aromatic amines ranging from 1:1 to 30:1 respectively. The resulting precipitate is separated from the purified waste waters. The aromatic isocyanates can be introduced into waste waters as solutions in inert organic solvents. The process of this invention can be useful in processes for the production of aromatic amines and derivatives thereof, for example aromatic isocyanates.